SGA; Anaemia in pregnancy Flashcards
What defines a fetus as being SGA, VSGA and LBW? [3]
How do you measure this? [2]
Small for gestational age
- is defined as a fetus that measures below the 10th centile for their gestational age.
VSGA:
- < 3rd centile
LBW:
- < 2500g
Assessed using:
* Estimated fetal weight (EFW)
* Fetal abdominal circumference (AC)
What are the two main causes of SGA? [2]
Constitutionally small, matching the mother and others in the family, and growing appropriately on the growth chart
Fetal growth restriction (FGR), also known as intrauterine growth restriction (IUGR)
TOM TIP: It is important to note the difference between small for gestational age (SGA) and fetal growth restriction (FGR).
What is this difference? [1]
Small for gestational age simply means that the baby is small for the dates, without stating why. The fetus may be constitutionally small, growing appropriately, and not at increased risk of complications.
Alternatively, the fetus may be small for gestational age due to pathology (i.e. FGR), with a higher risk of morbidity and mortality.
The causes of fetal growth restriction can be divided into two categories.
What are they? [2]
Placenta mediated growth restriction
Non-placenta mediated growth restriction, where the baby is small due to a genetic or structural abnormality
What are 4 causes of non-placental mediated growth restriction? [4]
Non-placenta medicated growth restriction refers to pathology of the fetus, such as:
* Genetic abnormalities
* Structural abnormalities
* Fetal infection
* Errors of metabolism
What are causes of placental mediated growth restriction? [+]
Placenta mediated growth restriction refers to conditions that affect the transfer of nutrients across the placenta:
* Idiopathic
* Pre-eclampsia
* Maternal smoking
* Maternal alcohol
* Anaemia
* Malnutrition
* Infection
* Maternal health conditions
Short term complications of fetal growth restriction include: [4]
Fetal death or stillbirth
Birth asphyxia
Neonatal hypothermia
Neonatal hypoglycaemia
Growth restricted babies have a long term increased risk of: [4]
Cardiovascular disease, particularly hypertension
Type 2 diabetes
Obesity
Mood and behavioural problems
How do you monitor for SGA?
RCOG green-top guidelines on SGA (2013) lists major and minor risk factors. At the booking clinic, women are assessed for risk factors for SGA.
Low risk women:
- monitoring of the symphysis fundal height (SFH) at every appointment from 24 weeks. If < 10th centile - booked for serial growth scans with umbilical artery doppler
Women are booked for serial growth scans with umbilical artery doppler if they have [3]
Three or more minor risk factors
One or more major risk factors
Issues with measuring the symphysis fundal height (e.g. large fibroids or BMI > 35)
How do you monitor SGA for those who are deemed high risk? [3]
Estimated fetal weight (EFW) and abdominal circumference (AC) to determine the growth velocity
Umbilical arterial pulsatility index (UA-PI) to measure flow through the umbilical artery
Amniotic fluid volume
Babies are defined as being large for gestational age (also known as macrosomia) when the weight of the newborn is more than [] kg at birth.
Babies are defined as being large for gestational age (also known as macrosomia) when the weight of the newborn is more than 4.5kg at birth.
What are the risks to baby for being LGA? [4]
The risks to the baby include:
* **Birth injury **(Erbs palsy, clavicular fracture, fetal distress and hypoxia)
* Neonatal hypoglycaemia
* Obesity in childhood and later life
* Type 2 diabetes in adulthood
When a baby is LGA - why do you perform US? [1]
Ultrasound to exclude polyhydramnios and estimate the fetal weight
Women are routinely screened for anaemia twice during pregnancy.
When are these screenings? [2]
Booking clinic
28 weeks gestation
Label A-C [3]
A - > 110 g/l
B: > 105 g/l
C: > 100 g/l
